Salesforce.com CEO Marc Benioff has managed to turn an Oracle slight into a nice little piece of publicity, vowing that his scheduled keynote at the OpenWorld conference would go ahead in a nearby hotel.

Not content with stirring up trouble with IBM, Oracle CEO Larry Ellison also decided to annoy Benioff by cancelling his slot at the conference at the last minute.

"I don't know why... Larry just cancelled my keynote tomorrow!" Benioff tweeted yesterday, adding "The show must go on!" in further tweets urging the crowds to join him at the St Regis Hotel in San Francisco today at 10.30am Pacific Time (18.30 GMT) instead.

Oracle emailed the New York Times to say that the cancellation was purely due to the crowds at the conference.

"Due to the overwhelming attendance at Oracle OpenWorld, we had to make several session changes. The Salesforce.com Executive Solution Session was moved to Thursday at 8am in the Novellus Theatre," the canned statement said.

As far as Benioff is concerned, that's as good as a cancellation, since "the show is over by then". He told Oracle he wouldn't be able to make that slot and set up his speech at the St Regis, a hotel a few steps away from the conference.

OpenWorld isn't quite over on Thursday, there are still seminars scheduled, but Oracle is having a free concert on Wednesday night for conference attendees, which means anyone who makes the 8am slot the next day probably won't be on their top form.

Despite Oracle's excuses, rumours abound that the reason for the snub is that Ellison's own keynote on Sunday night was a less than resounding success, and Benioff pointed out this fact on his Twitter account.

Benioff retweeted one tech commentator's review, which read: "What we saw today from Larry Ellison was abysmal. And shows why Salesforce under Benioff has captured the zeitgeist...".

He might have got away with that as a bit of flagrant self-promotion, but he also retweeted this comment from a software blogger: "How do you tell your founder CEO that his keynote sucks. Oracle marketing has a tough job."

But Benioff appears undaunted by the whole thing.

"Sorry Larry, the cloud can't be stopped," he told Ellison in his press release announcing the new venue for the speech.